I found this interesting table on Trend's website which takes the number of spam messages it receives, extrapolates it to estimate total worldwide spamming from an IP range and then reports on the range.
The bottom line is that they estimated that SAIX users (corporate, dial up, sub-ISPs, etc) all sent out about 82 Million spam emails in the last 24 hours making SAIX the 88th worst spam network in the world.
It is scary that so many spams are originating in sunny South Africa. Since spammers use unsuspecting PCs to do their dirty work this hints that there are many computers that have been compromised.
Its time for South Africa to take Information Security seriously.